Proposal for a Standard Echocardiographic Tricuspid Valve Nomenclature
Abstract
Objectives
The purpose of this study was to introduce a novel clinically relevant nomenclature system for the TV and determine the relative incidence of each morphological type.
Background
With the rapid development of transcatheter tricuspid valve (TV) repair techniques, there is a growing recognition of the variability in leaflet morphology and a need for a unified nomenclature, which could aid in procedural planning and execution.
Methods
Patients from 4 medical centers (2 in Europe, 2 in the United States) referred for transesophageal echocardiography (TEE) to assess native TV function, were retrospectively analyzed for leaflet morphology with the use of a novel classification scheme. Four morphological types were identified: type I, 3 leaflets; type II, 2 leaflets; type IIIA, 4 leaflets with 2 anterior; type IIIB, 4 leaflets with 2 posterior; type IIIC, 4 leaflets with 2 septal; and type IV, >4 leaflets.
Results
A total of 579 patients were analyzed: mean age 78.1 ± 8.0 years, 50.4% female, 70.9% in atrial fibrillation, and 32.2% with previous left heart surgery or transcatheter intervention. Tricuspid regurgitation was moderate or less in 9.4%, severe in 40.5%, massive in 32.3%, and torrential in 17.7%. The etiology of tricuspid regurgitation was primary in 9.4%, mixed in 10.8%, and secondary in all of the other patients (18.6% atriogenic/isolated). The incidence of type I morphology was 312 of 579 (53.9%), type II was 26 of 579 (4.5%), type IIIA was 15 of 579 (2.6%), type IIIB was 186 of 579 (32.1%), type IIIC was 22 of 579 (3.8%), and type IV was 14 of 579 (2.4%).
Conclusions
A novel TV leaflet nomenclature classification scheme can be used to identify 4 types of TV morphologies with the use of TEE imaging. From this multinational retrospective study, the TV has 3 well defined leaflets in only ∼54% of patients and 4 functional leaflets in ∼39% of patients, with type IIIB (two posterior leaflets) being the most common of the latter. The utility of this classification scheme deserves further study.